In recent years, the demand for securing safety of food, clothing, and housing has increased. In accordance therewith, the necessity for a raw material having flame retardant properties has increased. Under the circumstances, the demand for a textile having not only designability but also flame retardant properties has increased in the field of interior materials, especially in the field of chair upholstery.
In order to give designability to a textile, there is a method of producing a napped cloth using a design yarn referred to as a chenille yarn. However, the chenille yarn is likely to keep on burning because the napped part is in contact with a large amount of air. Thus, a cloth produced using the chenille yarn has a problem that the cloth is highly flammable.
Moreover, a method of giving flame retardant properties has conventionally been proposed which involves applying resin containing a flame retardant to the rear surface of a flammable cloth (e.g., Patent Document 1). However, when the flame retardant is adhered to the cloth as described above, there are problems that the cloth is whitened or the cloth becomes sticky under the effect of the flame retardant. Furthermore, in such a cloth, the cloth is sometimes discolored, stiffened, or reduced in volume in a napped part by the processing heat. Moreover, such a cloth has disadvantages that the frame retardant performance of the cloth decreases with time due to exposure to daylight, moisture absorption, etc., or, when the cloth is washed with water or dry-cleaned, the flame retardant is removed, resulting in loss of the frame retardant effect. In particular, a chair in which a flammable urethane foam is used as an internal padding and the padding is covered with a cloth to which a flame retardant has been adhered requires a lot of flame retardants for securing flame retardant properties. Thus, such a chair is limited in the designability and the comfortableness and moreover has a disadvantage in the cost. Thus, the cloth to which the flame retardant has been adhered has not been satisfactory in terms of the designability or flame retardant properties.
Moreover, a flame retardant polyester fiber and a fabric using the flame retardant polyester fiber have been proposed (e.g., Patent Documents 2 and 3). However, the cloth using the flame retardant polyester fiber is easy to make a big hole at the time of combustion due to melting of polyester fiber. Therefore, in the case of a chair in which an internal urethane foam is covered with the cloth, the urethane foam is ignited, and thus the flame retardant properties is not sufficiently secured.
In addition, a cloth using a flame retardant acrylic fiber has been proposed (e.g., Patent Documents 4, 5, and 6). However, also in the case of a cloth using the flame retardant acrylic fiber, a fabric in which a weaving yarn using a polyester fiber which is most advantageous in cost, designability, and productivity and widely used is used for a warp sometimes opens a hole due to the melting of polyester fiber and shrinkage or thermal decomposition of the flame retardant acrylic fiber at the time of combustion, and there is room for improvement. Moreover, in the case of the cloth using the flame retardant acrylic fiber, a polyester fiber has been required to be used as a composite fiber, such as a union yarn. Therefore, the flame retardant acrylic fiber was not able to widely use as chair upholstery.
Further, as a material which blocks combustion, a crosslinked highly flame-retardant acrylic fiber in which a thermally crosslinked polymer and an antimony oxide are added to the flame retardant acrylic fiber has also been proposed (e.g., Patent Document 7). The crosslinked highly flame-retardant acrylic fiber appears to demonstrate an effect in a state where the fabric is slackened. However, in the case where the crosslinked highly flame-retardant acrylic fiber is used for covering an urethane foam or the like similarly when used as, for example, chair upholstery, and then combusted, tension is applied to the fiber, resulting in that the fiber is likely to make a hole due to the shrinkage of the fiber similarly as another acrylic fiber and the urethane foam is ignited. Therefore, the flame retardant properties have not been sufficiently secured only by the use of the crosslinked highly flame-retardant acrylic fiber.
Patent-Document 1: Japanese Unexamined Patent Application Publication (Translation of PCT application) No. 2005-522532
Patent-Document 2: Japanese Unexamined Patent Application Publication No. 2003-166121
Patent Document 3: Japanese Unexamined Patent Application Publication No. 10-72743
Patent-Document 4: Japanese Unexamined Patent Application Publication No. 10-259542
Patent-Document 5: Japanese Unexamined Patent Application Publication No. 11-1842
Patent-Document 6: Japanese Unexamined Patent Application Publication No. 2003-201642
Patent-Document 7: Japanese Unexamined Patent Application Publication No. 2005-179876